Apparatus for proportioning the flow of gases



Feb. 11, 1936. L DAY 2,030,140

APPARATUS FOR PROPORTIONING THE FLOW OF GASES Filed April 5, 1935/NVENTO/? Zufherff" Day 5 5) FJE- w ATTORNEY Patented Feb. 11, 1936UNITED STATES PATENT OFFICE APPARATUS FOR PROPORTIONING THE FLOW OFGASES ration of Delaware Application April 3, 1935, Serial No. 14,397

15 Claims.

10 of the dynamic forces of the two streams; to

provide simple and practical means-adapted to be controlled by saiddevice for automatically maintaining proportional flow of the twostreams I irrespective of the difference in pressure of'the 15 twostreams; and to provide apparatus of the character indicated which shallbe particularly well adapted for controlling .delivery of air and fuelgas to gas-fired furnaces in cases where the fuel gas is under pressureand the air flows 20 to the furnace by induced draft as by stack draft.According to the present invention, the device which is responsive tovariation in ratio of the dynamic forces of the two streams comprises apivoted vane member provided with two vanes 25 that severally extendwithin the two conduits and across the streams flowing therein, theareas of the vanes being severally less than the cross sectional areasof. the conduits whereby the streams flow in continuous courses throughthe conduit 30 and around the vane and variations in ratio in theIdynamic forces effect turning of the vane mem- The manner of utilizingsaid device for automatically maintaining proportional flow of the 35two gases will more fully appear from the detailed description taken inconnection with the accompanying drawing wherein the various features ofnovelty and invention are shown.

Fig. 1 shows the invention applied to a gas- 40 fired furnace; Fig. 2 isa detail sectional view of certain features of the invention;

Fig. 3 is a. detail sectional view on line 3-3 of Fig. 2; 45 Fig. 4 is adetail sectional View of parts shown in Fig. 1, and

Fig. 5 is a diagrammatic showing of certain features of the invention.

Referring to Fig. 1, l indicates the wall of a 50 gas-fired furnace,such as a boiler furnace, for

example. Mounted in the furnace wall is a burner block ll having ports I2 for the admission of air and gas to the furnace chamber. 'Ihe'gas isdischarged from nozzles l3 in alignment with 55 the several ports, thenozzles forming part of a header M to which'gas under pressure issupplied by a conduit l provided with a ilow controlling valve Hi. Themain gas supply pipe is indicated at l5. The burner arrangement thus fardescribed is well known in the art and is intended 5 to be illustrativeof any preferred type of industrial gas burner.

Extending from the front side of the furnace wall I0 is an air box orconduit ll through which air for supporting combustion of the gas flows.to the burner. In the conduit is positioned any preferred flowadjusting device shown as louvers l8. In steam boiler practice, theposition of the louvers will ordinarily be controlled by a device PTwhich is responsive to steam pressure, as will be readily understood bythose skilled in the art. Insofar as the present invention is concerned,it is immaterial whether the air is delivered to the air box by a bloweror whether it flows to the box under the influence of stack draft.

A portion of the gas conduit l5 inside of the air box I! comprises aspecial fitting 20 to the underside of which is secured a detachablesupport or bracket 2L. Rotatably supported in this bracket is ahorizontally disposed rotatable shaft 22. Secured to one end of theshaft and extending upwardly therefrom into the fitting 20 is an arm 23to the upper end of which is secured a vane 24 of substantial butsufficiently small area to permit the free flow of gas past the vane.Secured to theother end of the shaft and depending therefrom into theair box I! is an arm 25 to the lower end of which is secured a vane 26of substantial but sufficiently small area to permit the free flow ofair past the vane. The effective length of the arm 25 may be varied ascircumstances require by releasing a set screw 21in the end of theshaft.

The relative areas of the vanes 2d and 26 and the distance of the vane26 from the shaft 22 are such that when the flows of air and fuel gasare in proper proportional relation, the arm 25 hangs vertically. Whenthe arm is in that position, the shaft 22 may be said to be in neutralor normal position. It will, of course, be readily appreciated thatincrease or decrease in the flow of 'one of the fluids withoutcorresponding change in the flow of the other fluids will cause a theshaft to turn.

Supported on the bracket 2|, as on a ledge 30 extending therefrom, aretwo opposed jet-orifice nozzles 3| and 32. These nozzles are connectedby pipes Ma and 321) respectively to a common supply pipe 33 for gaseousfluid under pressure. As a matter of convenience, the said fluid willordinarily be gas from the main supply pipe l ahead of the valve I6. Theconnection between the pipe 33 and the two pipes 3Ia and 32a preferablycomprises a block 34 having two separate passages 3lb and 32b, each ofwhich is in open communication with the supply pipe 33 through a.relatively restricted passage 35. Extending from the passages 3H; and32b .are pipes 3lc and 320 respectively. The pipe 3lc leads to apressure chamber 3ib at one side of a diaphragm 36, and the pipe 32cleads to a similar chamber 3211 at the other side of the same diaphragm.

The flow of the gas from the nozzles 3i and 32 is controlled by meanspositioned between the nozzles and movable with thevane shaft 22. Thismeans may comprise one but preferably comprises two spring fingers 31and 38, one for each nozzle, secured to and projecting upwardly fromsaid shaft. These fingers are so arranged that when the vane arm 25hangs vertically, they are equally remote from their respective nozzles,thus permitting equal flow of gas from both nozzles; it being understoodthat as long as the flows are equal, the pressures at opposite sides ofthe diaphragm 36 will be equal, since both sides are in connection withthe common pressure pipe 33. When, however, the fingers are moved out ofvertical position by the shaft 22, that finger which is closest to itsnozzle will restrict the flow of gas therefrom and thus cause adifference in pressure at the diaphragm with the obvious result ofcausing the diaphragm to move in the direction of low pressure. The gasvented from the nozzles 3| and 32 is conveniently conducted toward theburner by a vent pipe 42 leading from a cover 43 over the nozzle.

The function of the diaphragm is to effect change in position of the gascontrol valve IS in accordance as more or less gas is required to flowto the burner to maintain the desired air-gas ratio under changingconditions of air due, for example, to a change in position of thelouvers I8 or to a change in furnace draft or to other conditionsaffecting the flow of air to the burner. Ordinarily the valve l6 will becoupled directly to the diaphragm for movement therewith; but, it iswithin the spirit of the invention to control the operation of the valveby electrical means under the control of the same member, the fingers 31.and 38 of the latter in such case serving as switches for controllingthe electrical circuit.

In burner operation, it is not desirable that the flow of gas to theburner be 'entirelycut off by the operation of the controlling deviceand the valve i6 is therefore prevented from fully closing by anysuitable means such as an adjustable stop 4! supported in a dependingportion 40 of the diaphragm case.

Fig. 5 is a diagrammatic showing of how the vane member may be combinedwith electrical means for indicating change in proportional flow of thetwo gases flowing in the same direction in separate conduits I5a and Na.The vanes are indicated at 24a and 26a and the supporting shaft thereforat 22a. The same member serves as a switch for controlling two circuitsCI and C2 in each of which is a lamp or other device D which whenenergized will give notice of change from normal position of the vanemember. Ilia and la indicate valves or dampers for controlling the flowof one or the other of the gases as may be necessary to maintain thedesired proportional flow of the gases.

What I claim as new and desire to secure by Letters Patent is:

1. In apparatus of the class described, the combination comprising twoconduits, a turnable of said vanes being radially adjustable withrespect to the axis of rotation of the said member.

4. In apparatus of the class described, the combination comprising twoconduits, a turnable member provided with two vanes that severallyextend within the two said conduits and athwart the streams flowingtherein, the areas of the vanes being severally less than thecross-sectional areas of the conduits, whereby the streams flow incontinuous courses through the conduits and around the vanes andvariation in the dynamic forces effects turning of. the said member, andflow-regulating means in one of the conduits.

5. In apparatus of the class described, the combination comprising twoconduits, a turnable member provided with two vanes that severallyextend'within the two said conduits and athwart the streams flowingtherein, the areas of the vanes being severally less'than thecross-sectional areas of the conduits, whereby the streams flow incontinuous courses through the conduits and around the vanes andvariation in the dynamic forces effects turning of the said member,flow-regulating means in one of the conduits, and means operable by saidmember for controlling the operation of the said means,

6. In apparatus of the class described; the combination comprising twoconduits, a turnable member provided with two vanes that severallyextend within the two said conduits and athwart the streams flowingtherein, the areas of the vanes being severally less than thecross-sectional areas of the conduits, whereby the streams flow incontinuous courses through the conduits and around the vanes andvariation in the dynamic forces effects turning of the said member,flowregulating means in both of said conduits, and means operable bysaid member for controlling the operation of one of said means.

'7. In apparatus of the class described, the combination comprising twoconduits, a rotatable member provided with vanes that severally extendwithin the two said conduits and athwart the streams flowing therein,the areas of the vanes being severally less than the cross-sectionalareas of the conduits, whereby the streams flow in continuous coursesthrough the conduits and around the vanes and variations in ratio in thedynamic forces effect turning of said rotatable member, flow-regulatingmeans in one .of said conduits, and means for controlling the operationof said means including means through which a stream of fluid isnormally free to flow and also including a member carried by saidrotatable member for throttling the flow of the last named fluid.

8. In apparatus of. the class described, the comvanes being severallyless than the cross-sectional areas of the conduits, whereby the streamsflow in continuous courses through the conduits and around the vanes andvariations in ratio in the dynamic forces efiect turning of saidrotatable member, flow-regulating means in one of said conduits, andmeans for controlling the operation of said means including two fluidpressure pipes each having an outlet for the discharge of fluidtherefrom and also including means operable by said rotatable member forcontrolling the discharge of fluid through said outlets.

9. In apparatus of the class described, the combination comprising twoconduits, a rotatable member provided with vanes that severally extendwithin the two said conduits and athwart the streams flowing therein,the areas of the vanes being severally less than the cross-sectionalareas of the conduits, whereby the streams flow in continuous coursesthrough the conduits and around the vanes and variations in ratio in thedynamic forces effect turning of said rotatable member, a valve in oneof said conduits, means including a diaphragm for operating said valve,and means including a member movable with said rotatable member forapplying fluid pressure on one side or the other of said diaphragm.

10. In apparatus of the classdescribed, the combination comprising twoconduits, a rotatable member provided with vanes that severally extendwithin the two said conduits and athwart the streams flowing therein,the areas of the vanes being severally less than the cross-sectionalareas of the conduits, whereby the streams flow in continuous coursesthrough the conduits and around the vane-s and variations in ratio inthe dynamic forces effect turning'of said rotatable member, a valve inone of said conduits, means including a diaphragm for operating saidvalve,

two fluid pressure pipes leading from opposite side of said diaphragmand each having an outlet from which fluid is normally free to flow, andmeans movable with said rotatable memberfor controlling the discharge offluid from said pipes.

11. In apparatus of the class described, the

.combination comprising a conduit open at one end to the inflow of airfrom the atmosphere, a second conduit in communication with a supply offuel gas under pressure, a turnable member provided with two vanes thatseverally extend within the two conduits and athwart the streams flowingtherein, the areas of the vanes being severally less than thecross-sectional areas of the conduits, whereby the streams flow incontinuous courses through the conduits and around the vanes andvariation in the dynamic forces effects turning of the said member, aflow-regulating means in the second conduit, and means operable by saidmember for controlling the operation of the said means,

12. In apparatus of the class described, the combination comprising aconduit in communication with a source of gas under pressure, a valve insaid conduit, means including a diaphragm in a pressure case foroperating said valve, means including two opposed fluid discharge meansfor controlling the delivery of fluid under pressure to opposite sidesof said diaphragm,.' movable means arranged between said fluid dischargemeans and adapted when moved towards the latter to oppose the flow offluid therefrom, a second conduit for gaseous fluid, and means formoving said movable means including means responsive to variations inratio in the dynamic forces ofthe two streams flowing in the twoconduits.

13. In combination, two conduits, a flow-controlling device for at leastone of said conduits, a movable member for controlling the operation ofsaid device, means exposed to the dynamic force of the stream flowingthrough one of the conduits and tending under the influence of such,force to move said member in one direction, means exposed to the dynamicforce of the stream flowing through the other conduit and tending underthe influence of such force to move said member in the oppositedirection, neither of said means being effective to move said member solong as the difference between said forces remains constant.

14. In combination, two conduits, a flow-restricting device for at leastone of said conduits, mechanism including a rotatable shaft for controlling the operation of said device, means exposed to the dynamicforce of the stream flowing through one of said conduits and tendingunder the influence of such force to turn said shaft in one direction,means exposed to the dynamic 'force of the stream flowing through theother conduit and tending under the influence of such force to turn saidshaft in the opposite direction, neither of said means being efiectiveto turn said shaft so long as the difference between said forces remainsconstant.

, 15. In combination, two conduits, a flow-restricting device for atleast one of said conduits, a power-operated mechanism for controllingthe operation ofsaid device, a movable member for controlling theapplication of power to said mechanism, means exposed tothe dynamicforce of the stream flowing through one of said conduits and tendingunder the influence of such

